Effects of Bile Acids and Nisin on the Production of Enterotoxin byClostridium perfringensin a Nutrient-Rich Medium

Abstract

Clostridium perfringens is the second most common cause of bacterial foodborne illness in the United States, with nearly a million cases each year. C. perfringens enterotoxin (CPE), produced during sporulation, damages intestinal epithelial cells by pore formation, which results in watery diarrhea. The effects of low concentrations of nisin and bile acids on sporulation and toxin production were investigated in C. perfringens SM101, which carries an enterotoxin gene on the chromosome, in a nutrient-rich medium. Bile acids and nisin increased production of enterotoxin in cultures; bile acids had the highest effect. Both compounds stimulated the transcription of enterotoxin and sporulation-related genes and production of spores during the early growth phase. They also delayed spore outgrowth and nisin was more inhibitory. Bile acids and nisin enhanced enterotoxin production in some but not all other C. perfringens isolates tested. Low concentrations of bile acids and nisin may act as a stress signal for the initiation of sporulation and the early transcription of sporulation-related genes in some strains of C. perfringens, which may result in increased strain-specific production of enterotoxin in those strains. This is the first report showing that nisin and bile acids stimulated the transcription of enterotoxin and sporulation-related genes in a nutrient-rich bacterial culture medium.

Necrotic Enteritis in Broiler Chickens: The Role of Tight Junctions and Mucosal Immune Responses in Alleviating the Effect of the Disease

“…An in vitro study reported that production of enterotoxins by C . perfringens type A increases in the presence of bile acids, which are secreted in the upper parts of the small intestine [32]. This might be a reason for higher lesion scores in the duodenum and jejunum compared with the ileum in the current study.…”

Necrotic Enteritis in Broiler Chickens: A Review on the Pathogen, Pathogenesis, and Prevention

“…Subclinical necrotic enteritis is associated with hepatitis or cholangiohepatitis [ 102 ] and the gall bladder being distended with a flocculent substance [ 103 ]. Bile acids promote sporulation and enterotoxin production by C. perfringens [ 104 ], justifying the higher incidence of necrotic lesions in the upper parts of the small intestine, the duodenum, and jejunum.…”

Clostridium perfringens strains proliferate to high counts in the broiler small intestinal tract, in accordance with necrotic lesion severity, and sporulate in the distal intestine

“…Studies reported that in a Clostridoides difficile infected mouse-model, some secondary bile acids, such as deoxycholate (DCA) or taurocholate (TCA) induce spore germination, while others, such as lithocholate (LCA) or ursodeoxycholate (UDCA), are inhibitory (Winston and Theriot, 2016). Additionally, bile acids have previously been shown to stimulate C. perfringens spore formation in vitro (Heredia et al, 1991;Park and Rafii, 2018).…”